Current Regulator for Solid State Lighting Dimmer Compatibility
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LED drivers are incompatible with phase-modulating dimmer switches, leading to operational issues such as flicker, inrush currents, and instability when used with incandescent and LED lamps in parallel, requiring complex and costly solutions that are inefficient and incompatible with existing lighting infrastructure.
Innovation Solution
A current regulator with an impedance matching circuit and a controller that adjusts the duty cycle based on RMS voltage levels, allowing for seamless operation with phase-modulating dimmer switches and enabling parallel operation with incandescent lamps, using a switching power supply and active impedance matching to maintain stable triac firing and reduce power loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing LED drivers are used with phase-modulating dimmer switches, then LED power supply is provided, but instability and electromagnetic interference occur
Solution Approach 1:
The patent introduces an intermediary circuit between the phase-modulating dimmer switch and the LED driver that conditions the incoming power signal. This intermediary circuit filters and regulates the phase-modulated power before it reaches the LED driver, eliminating electromagnetic interference while maintaining operational stability. The intermediary acts as a buffer that translates the dimmer's control signals into stable LED-compatible power.
2Adaptability or versatility
If existing LED drivers are used without impedance matching, then simple circuit design is achieved, but compatibility with phase-modulating dimmer switches is lost
Solution Approach 1:
The patent implements dynamic impedance matching that automatically adjusts the input impedance of the LED driver to match the output impedance of the phase-modulating dimmer switch. This dynamic adaptation allows the circuit to maintain compatibility across different dimmer switches and operating conditions without requiring complex manual configuration or multiple fixed-impedance circuits.
3Reliability
If LED drivers are designed for constant current output, then LED protection is improved, but integration with existing lighting infrastructure requires rewiring
Solution Approach 1:
The patent designs the LED driver with multi-functionality to operate in multiple modes: it can function as a constant current driver for LED protection, while simultaneously providing impedance matching and phase-modulation compatibility for integration with existing lighting infrastructure. This universal design eliminates the need for rewiring by accommodating both protection requirements and infrastructure compatibility within a single device.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution enables efficient, stable, and cost-effective operation of LED drivers with phase-modulating dimmer switches, reducing flicker and inrush currents, and allowing for integration with existing lighting systems without rewiring, providing consistent brightness control and energy savings.
Implementation Method 1
a switching power supply providing a first current
Implementation Method 2
an impedance matching circuit coupled to the switching power supply and couplable to the phase-modulating switch or to the AC line voltage, the impedance matching circuit adapted to provide a second current through the phase-modulating switch when a magnitude of the first current is below a first predetermined threshold
Implementation Method 3
the controller adapted to determine a root-mean-square (RMS) voltage level provided by the phase-modulating switch from the AC line voltage, and to determine a duty cycle for pulse-width current modulation by the switching power supply in response to the comparison of the RMS voltage level to a nominal voltage level
Implementation Method 4
determine a duty cycle for pulse-width current modulation by the switching power supply
Data Source
AI summary
An exemplary embodiment provides a current regulator for controlling variable brightness levels for solid state lighting. The current regulator is couplable to a phase-modulating switch, such as a dimmer switch, which is coupled to an AC line voltage. An exemplary current regulator includes a rectifier; a switching power supply providing a first current; an impedance matching circuit; and a controller. The impedance matching circuit is adapted to provide a second current through the phase-modulating switch when a magnitude of the first current is below a first predetermined threshold, such as a holding current of a triac of the phase-modulating switch. The controller is adapted to determine a root-mean-square (RMS) voltage level provided by the phase-modulating switch from the AC line voltage and to determine a duty cycle for pulse-width current modulation by the switching power supply in response to the comparison of the RMS voltage level to a nominal voltage level.